Steamboat Springs  Things were peachy. The Steamboat Springs High School boys lacrosse team was in complete control.

The team was winning face-offs, ground balls and scoring at will.

Then, the second half started.

In what amounted to an utter collapse, Steamboat lost composure and, eventually, the game. Valor Christian won, 11-10.

By all accounts, Steamboat was in control through the first two quarters. The Sailors were up 5-0 after the first in what was one of their finest quarters of the season. The team took an 8-2 lead into halftime. It seemed the only question remaining was whether it would get to a running clock.

Then it was like the two teams traded jerseys. Valor outscored Steamboat 7-1 in the third quarter, with Ryan Russell’s goal at the buzzer knotting it at 9-all going into the fourth.

“The win means more to us than you can imagine,” Valor coach Chris Deutschman said. “I’ve never been more proud of a group of guys.”

It speaks to the turnaround in halves. In the first, Steamboat was dominant. The Sailors cruised to a 5-0 lead with three goals from Ben Wharton and one each from Peter White and Mitch McCannon.

The second was a similar tale. Steamboat controlled play and went into halftime in a comfortable position.

Whereas the first period was one of Steamboat’s best, the third arguably was its worst.

Valor scored the first four of the period — two from Logan Bruss and one each from Russell and Josh O’Connell — to cut it to 8-6.

After White made it 9-6, Bruss and Russell closed the period with three goals to tie it heading to the final frame.

The ground balls and face-offs Steamboat had been winning shifted to Valor. The Sailors also lost their cool. Three penalties in the quarter allowed Valor to maintain momentum.

The Eagles went 3 for 3 on the man up in the quarter and were 4 of 6 overall.

“Things started to spiral a little, and I think panic set in,” Steamboat coach Bob Hiester said. “I think we got a little complacent at half.”

It was still a game in the fourth, but the Eagles’ Cole Baker gave Valor its first lead of the game early in the fourth. Bruss added another to make it 11-9 before White scored a man up goal with 21 seconds left to cut the lead to 11-10.

Steamboat won the face-off, but Valor intercepted a pass and was able to run out the clock.

“After the first half, there was this aura of negativity,” Deutschman said. “Players were upset with players and their shoulders were hunched. I told them they needed to have a positive attitude. We wanted this one really bad.”

Steamboat (10-3) next plays at 4 p.m. at home May 2 against Summit. The team will have a scrimmage Thursday at Regis before being off for spring break.

How the game affects the team’s playoff seeding remains to be seen. A win likely would have garnered the team a top-five seed. Now, with weeks still left in the season, it becomes a guessing game.

“We just had a good discussion,” Hiester said. “They’re not doing a lot of finger pointing. We’ll fix what didn’t go well.”